Hi!
Mickel: Just that we don't have a misunderstanding there. After a real fight with goblins, lizard men, or maybe after major food riots, the fortress should be painted red in my opinion. I agree that it adds a lot to the flavor and really gives a good feeling for what is going on there.
Ah! I forgot to mention in my idea that each creature should have a "bloodondeath" value which states how much blood it could release upon death. So, an elephant you kill will still create enough blood to color your whole main corridor, as will four or five goblin raiders, but two rats just won't be enough.
My main gripe are those things that seem really out of scale. I mean, near the end of a season, I regularly have my main corridors completely red, even though no violence occured in my fortress. This is just because of a handful of rats my cats killed and whose blood gets spread throughout the entire fortress.
Having channels stop blood spread is also a consideration because of the double engravings. Even if a room is far away from a fight or anything, there is still a good chance that blood will reach it from the other end of the fortress. This is why I think that especially recreation areas or tombs should be protectable against such excessive blood.
Deathworks